Biofuels produced from living organisms such as plants and algae are alternative fuels to those derived from petroleum such as diesel and petrol. Algae are the preferred choice for producing biofuels as they are able to efficiently convert sunlight and carbon dioxide to biomass and synthesize lipids, and can grow in harsh environmental conditions. Many strains of algae produce triglycerides, which can be converted to biofuels.
Methods for increasing lipid content in microorganisms include nutrient-limitation, modulating enzyme activity, growing the microorganisms in a stress inducing environment and genetic engineering techniques. Though, these methods lead to an increase in lipid content, there is an overall decrease in the growth and cell-mass produced, which is undesirable.
It is known that a major amount of fixed carbon from photosynthesis is channeled to the production of proteins. Hence, decreased protein synthesis would lead to the utilization of this fixed carbon in making lipids, which can be used for the production of biofuels from the microorganisms, specifically from algae/cyanobacteria. The protein synthesis can be down-regulated and the carbon flux is redirected to the production of lipids.
Therefore, the inventors of the present disclosure envisage a method for decreasing the levels of protein synthesis in microorganisms whereby increased lipid content is obtained.
The disclosure also envisages modified strains of microorganisms such as algae and/or cyanobacteria having increased lipid content.